Ok, the error message is rather generic. It guess it could be an issue with your hardware network connection (but likely not as your crawl is working fine with other websites), or eventually this particular host could be rejecting requests from your YaCy peer for some reason.Does this website answers without error when you request it from the same computer on which you run YaCy, but with other tools such as a browser, curl, wget...?

Yes the website is reachable from the server where yacy is installed. May be a problem with ssl ? www.sabatino.pro is my website. The problem started after I changed the ssl certificate. Do you think it's only a coincidence ?

Yes it would be strange to be only a coincidence... But I have "good" news : I could reproduce the exact same issue as you when running YaCy 1.92/9000 with a Oracle JVM jdk1.7.0_80. I had no time yet to check in-depth what is exactly going wrong, but at least I can ensure you that everything works fine with the same YaCy release on a recent 1.8 JVM (OpenJDK or Oracle 1.8.0_151), so I suggest you to upgrade at least your Java version.

A few more details : your website appears to be configured to use TLSv1.2. By default TLSv1.2 and TLSv1.1 are disabled in the JDK 1.7 on client connections, while the JDK 1.8 uses TLSv1.2 as default. I tried to enable TLSV1.2 in my JDK 1.7 install, using the control panel, but still had no success to crawl then your website with a YaCy peer running on this Java version. So this makes one more good reason to upgrade to Java 1.8.